Year	Percent
1990	14.014
1991	13.833
1992	13.822
1993	14.188
1994	14.571
1995	12.505
1996	13.61
1997	14.839
1998	15.174
1999	15.488
2000	16.057
2001	15.953
2002	16.083
2003	16.95
2004	17.866
2005	19.344
2006	20.921
2007	21.102
2008	21.56
2009	22.817
2010	21.737
2011	22.092
2012	22.349
2013	22.622
2014	22.958
2015	23.921
2016	24.73
2017	24.927
2018	25.121
2019	25.305
2020	25.476
2021	25.633
2022	25.779
2023	25.917
2024	26.052
2025	26.186
2026	26.318
2027	26.451
2028	26.585
2029	26.721
2030	26.858